Double acting hydraulic jack



Dec. 18, 1934.

G. A. couNrrRYMAN 1,985,151

DOUBLE` ACTING. HYDRAULIC JACK I v Filed Aug. 12, 1935 82\ l 99 402 11- .1 I if* 2 A 'y '/10 LA 15 il 104 85 J ,e1 )o6 19 l f I l 1 1 .49 A

48 i 1 I Z0*r/ I 212 sz- 54 v 1 j ,Fly

2%'2 g e8\ l 5/ l5 ze 58 105 10/ @W Albmby/fzm Patented Dee. 1s, 1934l y. i y 1,985,151A

UNITED STATES PATENT OFFICE l DOUBLE Ac'rntssrrlrsilimuuc JACK t Guy A. countrymannshland, ohio Application August 12, i933, serial No. 684,873

' schim. (ci. 6o52i The invention relates to hydraulic jacks and the jack are preferably formed of duralumin or more especially to a double acting Jack which may other light weight alloy having suicient strength be selectively raised for lowered by hydraulic for the purposes for which the jack is intended power. i to be used.

5 An object of the improvement is to providea The jack may be mounted upon a base inthe 5 hydraulic jack adapted tobe driven by hydraulic form of a casting indicated generally at of power to eitherraise or lower the jack as desired. substantially oblong shape and having feet 11 Another object is to provide a jack of this charand 12 at opposite' ends for supporting the jack acter having a hydraulic cylinder, with a piston upon th ground or floor or other` substantially lo therein, and means for selectively admitting uid horizontal surface when used as a lifting jack. l0 to the cylinder upon either Side 0f the piston. e Located at the end of the base adjacent to the A further object is to provide such a jack with foot 11 is an upright annular ange 13 internally a Pair 0f Valves C0ntr01lin8 the raising and lowthreaded to receive the lower threaded end of ering o! the jack, the valves being operated in the hydraulic cylinder 15. The head 16 has the i5 unison So that one valve opens as the other closes. depending internally threaded ilange 1'1 xed l5 A still further object is t0 DI'OVid-e a lack having upon the threaded upper end of the cylinder 15 valves suchas above referred to, inwhich the and 9, packing ring 18of .inverted substantially valves are reversely Operated t0 Open or.c1osed channel cross section is located within the up- DOStiOn. and, in Which beth ValVeS may Simultawardly disposed annular ange 19 formed upon 20 neOUSly assume a neutral POSitiOn, whereby the the cylinder head 16, said packing ring surround- 2o Jack `may be lowered by the weight of the -body ing the piston rod 2o and being heldin place as lifted thereby. by the screw ring 21.

Another object of the invention is to provide The piston rod 20 has'` a shouldered portion a hydraulic :lack having a safety Valve WhiehA 22 iixed upon its lower portion, the end of the 2 5 Permits the return 0f the llld t0 the leSeI'VOi rod being reduced and threaded as at 23 and 25 in the event 1500 great a' lOad iS Placed 119011 the having the piston 24 held thereonby means of jack' the nut 25, clamping the two liber or leather A further object is to provide a hydraulic Jack washers 2 6 and the metal disk 27 therebetween, adapted for use in the straightening 0f autOmO- It will be noted that the washers 26 are proao bile frames and the like, the lack beine arranged vided with annular flanges 28, the :lange of the t0 Dull 11014510115 0f the autOmUbile frame toward upper washer extending between 4the periphery each otherlas well as to push lOpposite DOI'tiOnS 0f of the shouldered portion 22 and the 'interior A the frame away frOm One anothelof the cylinder while the peripheral ilange of the The abOVe Objects' weather with Others which lower washer is located between the piston 24 *Wm later appeal" may be attained by Constructing and the interior of the cylinder, thus assuring a 35 the improved Jack in the manner lllustlated ln tight fitting piston regardless of which side therethe aee0mDanyln8d1'aWln8,inWhih oi' the oil pressure ls'applied. f, Y y

Figure 1 is a vertical sectional view of the A boss 29 is formed upon the base at a point double .acting hydraulic leek embodying the 111-- speeed from the annular aange 13 and is pro- 4 o vennen. teken as on the line 1-1. Fis 2: vided with an internally threaded socket 3o into 40 F18- 315 Plan Sectional *View 0f the improved which is screwed the threaded `lower end oi the jack indicated as on ythe line 2 2, Fig. 1; pump cylinder 31, A

Fig. 3, a fragmentary transverse sectional view The pump is located within an oil reservoir taken as 0n the llneS 3 3, Fiss. 1 and 2; including the shell 33 concentrically located with F18- 4. a'. fragmentary transverse Sectional View 'reference vto the pump cylinder and having -i 45 taken as on the Aline 4 4, Fig. 2; and lower beveled end 34 received within i the an- Fl8 5, a fragmentary Sectional vView Showing nular rib 35 formed-'upon'the top -of the base, the connection of the fluid pipe from the pump to the inner side of said rib being beveled as at 36 the upper end of thejack cylinder. y to receive the end portion 34 of the shell.

Similar numerals .refer to similar -parts 'Ihe top wall 37 of the reservoir has a central 50 throughout the drawing. Y opening 38v surrounding the pump cylinder and The improved jack to which the invention peradepending peripheral ange 39 internally tains may be formed o! any suitable metal but threaded for engagement with the threadedupin order to make the same' sumciently light in per end oi the shell 33, which-together with the'- weight that it is easily portable, vthe parts ,ot top wall is held clamped upon the base by means 55 of a nut 49' mounted upon the threaded upper mally heldvdownward thereon as by a coil spring portion 41 of the pump cylinder.

The pumpplunger 42 is mounted within the cylinder 31 and has the ber or leather washer .43 .at its lower end provided with the peripheral ange l44, said washer being secured upon the lower end of the plunger as by the screw 45.

The plunger is slidably mounted through the stuiiing box 46 provided at the upper end of the pump cylinder 31 and a nut 47 is xed tothe? threaded upper end portion 48-of the plunger. Ears 49 may. be formed uponthenut 47 between which is received the handle lever 50 pivoted to the ears 49 as by the pin 5l, the'inner end of -said lever being pivote'd as by the pin -52 to the upper end of a link 53 pivoted at its lower end as at 54. upona lug 55 formed upon the top wall f 87 or other stationary portion of the apparatus.

.an inlet port 56 communicates with the lower end of the pump cylinder and leads to a horiaantal passage 57 formed in the base casting, plugged at one end as by the screw 58, the other end thereof communicating .with avertical passage 59, the upturned end 60 of which counifcates with the interior of the oil reservoir.

A valve seat 61 is formed in the passage 59 to receive the gravity operated ball check valve 62 which prevents oil from the pump from being forced back into the reservoir but permits oil from the'reservoir to be sucked into the pump.

A safety valve isprovided for overloading. fofthe jack and may comprise a tube 63 closed at its upper end as by the screw plug 64, the lower end thereof .communicating with the passage 59 above the ball 62. A valve seat 65 is formed in the tube 68, the check ball valve 66 being nor- 67, the tension on which maybe adjusted by the screw 64. Transverse openings 68 in the tube 63 form a communication between the interiorof the tube,

above the valve seat 65, and the interior of the oil reservoir 83. Thus, it a-load greater than thev capacity oi thejack is placed upon the jack, the ball 66 will be raised by the oil pressure from the pump, permitting the oil to ow through the apertures 68 back' into ft@ reservoir, thus pre- ,venting straining of the jack.

` l l' A discharge passage 69 communicates with the `|50 lower. end of the pump cylinder and leads down.

ward through. the base 10, communicating with the intermediate portion of a transverse passage ,79 which terminates' near one side o1' the base, the opposite end of the passage being closed as by the screw plug 71. y A valve seat 72 is formed in the passage 69 above the junction with the transverse passage 70 anda ball check valve73 is normallyheld vseated against said valve" seat by means of a coil spring '14," the' tension vupon vwhich may be adjusted as by the screw 75.

The longitudinauysispesed passages 'ze and '17 oomm'unicate with the transverse passage 70, these passages being each closed at one" end and having Q- valve seats 'I8 and '19 respectively at their open ends to receive the ball valves and 81 respec' tively, normally urged away from said valve seats asby the coil'springs 82.' Y v,

Transversely disposed'chambers'83 and 84 `communicate'with the open ends of the passages 76' and 77 respectively and with the inlet ports 85 and 86 leading to the' lower and upper ends respecv tively-of the hydraulic cylinder-15, the upper port 86 communicating with the vertical pipe 8 7 which s nsA leads to a radial inlet port 88 terminatingin the vertical passage `89,1'orm1ed inthe head 16. and

-seat 78 and the stem 191 ,being with adaptedto admit oil into the upper end of the cylinder 15 above the piston 22 and also to hold the packing ring 18 under pressure.

A pair of screw plugs 99 and 91 are mounted y ervoir 33.

The bore 92 oi each oi the screw plugs commu nicates with the corresponding transverse passage 83 or 8e, the screw plugs being provided at their ends with valve seats 97 and 98 respectively adapted to receive the ball valves 89 and 8l respectively.

- .fl portion of the bore of each screw plug is threaded to receive the threaded portions. 99 'of the Valve stems 199- and 191, which are adapted to contact with thel balls 89 andl 8l. respectively for the purpose of moving said balls away from the seats 97 and 98 and toward the seats 78 and 79. The stems 199 and 101 arepreferably arranged tobe simultaneously operated in reverse directions and this may be accomplished by means of the gears 102 fixed upon the stems and mesh= ing with each other. For the purpose of operat-s ing the stems, a handle 103 may be provided upon one stem whereby rotation thereof, through the gears 102, will operate both stems in oppositel directions., l

- With the parts in theposition shown in Fig. 2, the stem 109 vholding the ball 89 against the wn out of contact with the ball 81 so that the spring 77 holds said ball against the seat 98, it will be seen that as the lever 59 is operated, the pump will force duid through the passage 69, past the ball 78 and through the transverse passage 79.. The passage 76 being closed by the ball 89, the oil is forced from the transverse passagej through the passage '17 past the bau s1 into the upper ma let port 86, thence through the upright pipe 87 to the -upper end of the cylinder, forcing the l plunger 29 downward.

yBy rotating the stems and 101, by means of the handle 103, through the gearing 192, the stem 109. may be withdrawn from the ball 89 sufliciently to permit said ball to be moved away from the seat 78 but not against the seat 97 and the ball 81 will .at the same time assume a corresponding position, thus placing thev Jack in a neutral posi- -seat97while the ball 81 is seated against the seatl 'I9 whereby the operation of the pump plunger will torce .the `iiuid vfrom the pump through the passage 69 and ktransverse passage 70 and longitudinal passage F16, past the ball 80 and through the lower'inlet port 85 to the bottom oi the jack cylinder 15v below the piston thereof. raising the plunger\20. l

For therpurpose of lack for s 'It-75l ening automobile frames yand the. like, the base 10 may be provided with an internally threaded frame or the like whereby the same may be draw together or forced apart as desired.

It should be understood that instead of the particular ball valves 80 and 81 and threaded stems geared together for operating the same, any arrangement of valves reversely operated to close -one valve and simultaneously open the other or to bring both valves to neutral position may be provided for accomplishing the invention without departing from the spirit thereof.

I claim:

1. A hydraulic jack including a cylinder, a plunger in the cylinder, a pump, an oil reservoir, passages forming communication between opposite ends of the cylinder and the pump, spaced valve seats in each passage, a communication between each of said passages and the oil reservoir, a valve in each passage, ar-

ranged to selectivelyuseat vagainst either valve" tween each passage and the'oil reservoir, a single j '-ballvalve in each passage arranged to selectively seat against either valve seat, al spring normally urging each-ball valve into a position against one seat to permit uid from the pump to pass to the cylinder, a stem for contact with each ball to. move the sameo against the pressure ofthe spring to a position againstthe other valve seat, and means for Vsimultaneously operating said stems in reverse directions to selectively divert fluid from the pump through one passage to the cylinder and through the other passage tothe oil reservoir.

3. A hydraulic jack including a cylinder, a plunger in the cylinder, a pump, an oil reservoir, passages forming communication between oppo-v site ends of the cylinder and the pump, spaced valve seats in each passage, a communication between each passage and the oil reservoir, a single ball valve in each passage arranged to selectively seat against either valve seat, spring normally urging each ball valve into a position against one valve seat to permit iluid from the pump to pass to the cylinder, a stem for contact with each ball to move the samey against the pressure of the spring to a position against the other valve seat, and means for simultaneously operating said stems to alternately seat said valves against `oppositely disposed seats, and to move both valves to neutral position away from both valve seats whereby the plunger may be lowered by the weight of a load thereon.

4. A hydraulic jack including a cylinder, a plunger in the cylinder, a pump, an oil reservoir. passages forming communication between opposite ends of the `cylinder and the pump, spaced valve seats in each passage, a communication between each of said passages andthe oil reservoir, a single ballA -valve in each passage arranged to selectively engage either valve seat, a spring for normally urging each ball to a position against one valveseat to lpermit iluidv from the pump to pass to the cylinder, a screw threaded 'stem for contact with each ball to move t'he same against the pressure of the spring to a position against the other valve seat, and meshing gears upon said stems for simultaneously operating said stems in reverse direction to selectively operate -sure from the pump.`

5. A hydraulic jack including a cylinder, a

plunger inthe cylinder, a pump, an oil reservoir,

passages forming communicationbetween opposite endsof the cylinder and the pump, spaced valve seats in eachpassage, a communication between each of said passages and the oil reservoir, a singleI ball valve in each passage arranged to selectively engage either valve seat, a spring forV normally urging each ball to Aa position against onev valve seat to permit nuid from the pump to pass to the cylinder,r a screwv threaded lstem for contact with eachball to move the same 

